The present invention relates to a new and distinct tree variety of Sequoia sempervirens, more commonly known as Coast Redwood tree, having naturally-occurring chimeric characteristics resulting in albinism vegetation.
Specifically, ‘Early Snow’ is a periclinal chimera exhibiting stable albino growth inside the apical meristem dome. The albinism emerges more prominently beginning in the first or second year of growth. Tests conducted by the first-named inventor reveal that the present invention has a survival tolerance with up to 65 to 70 percent albinism. The buds of the present invention contain several forms of naturally-occurring chimera, including: periclinal, mericlinal, and sectorial. The branches demonstrate color variation, including: green, albino, and chimeric, and non-chimeric variegation; and exhibit a horizontal-to-moderate drooping growth habit. Needle morpholgy exibits a dense, occasionally overlaping habit that is singularly arranged with a concave pattern. Additionally, certain favorable conditions, the present invention yields high propagation levels via stem and leaf cuttings.
The new variety originated as a result of an ongoing breeding program in Santa Cruz, Calif. The seedling of the present invention was grown from a controlled cross conducted in 1976 where an unnamed, unpatented albino Sequoia sempervirens providing the male pollen and the conelets of an unnamed, unpatented green Sequoia sempervirens were pollinated. After repeated experimental propagation efforts, asexually-reproduced leaf and stem cuttings took root in a greenhouse laboratory setting in Volcano, Calif. between the years of 2012-2015. These cuttings yielded the stable periclinal chimeric albinism growth characteristic of the present invention.
Coast redwood trees (hereinafter “redwood”) are well known in the industry for their disease and insect resistance, fast growth habit, fire tolerance, and for supporting wildlife habitat. Redwoods are also noted for their height and longevity. These characteristics have led to an increase of the use of this plant as an ornamental feature in landscaped gardens and re-forestation projects. Congruent with similar coast redwoods, the present invention is expected to reach a height of 18 to 36 meters, maintain tree form, and have a lifespan capacity of 200 to 1000 years.
Albinism in redwoods is a genetic mutation presenting chlorophyll deficiency in the plant's needles and stems. As chlorophyll is instrumental to glucose production and storage, albinism prevents a plant from providing food for itself; therefore, survival of albino growth is depended upon parasitic-type growth on the non-albino portions of the redwood. Albino redwoods (hereinafter “albino”) in the wild are typically found in two forms: aerial and basal. Aerial albinos consist of a mutated branch where the foliage grows white or yellow. Basal albinos consist of entirely white or cream colored basal sprouts growing off an otherwise healthy green redwood. A chimeric redwood is a single plant organism with two or more different genotypes originating from the same bud or meristem. The normal green genotype acts as a surrogate to support the growth and survival of the albino mutation. It is not a symbiotic relationship between two separate plants. Further, due to this dependency and lack of chlorophyll, pure albino redwoods are unable to be reproduced vegetatively.
White color variation is subject to environmental conditions, particularly light exposure. For example, when grown in direct sunlight conditions, albino redwoods may turn ivory, cream, or light yellow in color. In contrast, when growing under the canopy of surrounding tree branches, albino redwoods are white in color. Excessive heat and low humidity may also result in die-back of the albino portions of the redwood. Additionally, the variation and distribution of white coloration is influenced by the phenotypic expression of three different types of chimeric growth: periclinal, sectorial, and mericlinal.
Chimerism in plants is typically achieved artificially through grafting and controlled gamma ray irradiation of seeds. One example of a grafted chimera plant is the thornless rose. A second example of irradiated seeds producing chimeric growth is the African violet plant. The present invention, in contrast, is a naturally-occurring chimeric mutation observed through variegated apical stems.